Structural and functional insights into the cardiac Na+/H+ exchanger

► Structural studies of the mammalian Na+/H+ exchanger protein have begun. ► Transmembrane segments of NHE1 were interrupted helices. ► The extended regions often contained amino acids critical in function. ► Several transmembrane segments of NHE1 were similar to those in E. coli NhaA. ► NHE1 may have significant similarities in transport mechanism to NhaA.